1 /*************************************************
2 * Exim - an Internet mail transport agent *
3 *************************************************/
5 /* Copyright (c) Jeremy Harris 2014 */
7 /* This module provides TLS (aka SSL) support for Exim using the OpenSSL
8 library. It is #included into the tls.c file when that library is used.
14 #include <openssl/lhash.h>
15 #include <openssl/ssl.h>
16 #include <openssl/err.h>
17 #include <openssl/rand.h>
18 #include <openssl/x509v3.h>
21 /*****************************************************
22 * Export/import a certificate, binary/printable
23 *****************************************************/
25 tls_export_cert(uschar
* buf
, size_t buflen
, void * cert
)
27 BIO
* bp
= BIO_new(BIO_s_mem());
30 if ((fail
= PEM_write_bio_X509(bp
, (X509
*)cert
) ? 0 : 1))
31 log_write(0, LOG_MAIN
, "TLS error in certificate export: %s",
32 ERR_error_string(ERR_get_error(), NULL
));
40 if ((n
= BIO_gets(bp
, cp
, (int)buflen
)) <= 0) break;
43 cp
[-2] = '\\'; cp
[-1] = 'n'; /* newline->"\n" */
44 } /* compat with string_printing() */
53 tls_import_cert(const uschar
* buf
, void ** cert
)
55 void * reset_point
= store_get(0);
56 const uschar
* cp
= string_unprinting(US buf
);
61 bp
= BIO_new_mem_buf(US cp
, -1);
62 if (!(x
= PEM_read_bio_X509(bp
, NULL
, 0, NULL
)))
64 log_write(0, LOG_MAIN
, "TLS error in certificate import: %s",
65 ERR_error_string(ERR_get_error(), NULL
));
71 store_reset(reset_point
);
76 tls_free_cert(void * cert
)
78 X509_free((X509
*)cert
);
82 /*****************************************************
83 * Certificate field extraction routines
84 *****************************************************/
86 /* First, some internal service functions */
91 expand_string_message
= US
"allocation failure";
96 bio_string_copy(BIO
* bp
, int len
)
99 len
= len
> 0 ? (int) BIO_get_mem_data(bp
, &cp
) : 0;
100 cp
= string_copyn(cp
, len
);
106 bio_string_time_to_int(BIO
* bp
, int len
)
110 len
= len
> 0 ? (int) BIO_get_mem_data(bp
, &cp
) : 0;
111 /*XXX %Z might be glibc-specific? */
112 (void) strptime(CS cp
, "%b%t%e%t%T%t%Y%t%Z", &t
);
114 /*XXX timegm might not be portable? */
115 return string_sprintf("%u", (unsigned) timegm(&t
));
119 asn1_time_copy(const ASN1_TIME
* time
, uschar
* mod
)
121 BIO
* bp
= BIO_new(BIO_s_mem());
124 if (!bp
) return badalloc();
126 len
= ASN1_TIME_print(bp
, time
);
127 return mod
&& Ustrcmp(mod
, "int") == 0
128 ? bio_string_time_to_int(bp
, len
)
129 : bio_string_copy(bp
, len
);
133 x509_name_copy(X509_NAME
* name
)
135 BIO
* bp
= BIO_new(BIO_s_mem());
138 if (!bp
) return badalloc();
141 X509_NAME_print_ex(bp
, name
, 0, XN_FLAG_RFC2253
) >= 0
143 return bio_string_copy(bp
, len_good
);
147 /* Now the extractors, called from expand.c
150 mod Optional modifiers for the operator
153 Allocated string with extracted value
157 tls_cert_issuer(void * cert
, uschar
* mod
)
159 uschar
* cp
= x509_name_copy(X509_get_issuer_name((X509
*)cert
));
160 return mod
? tls_field_from_dn(cp
, mod
) : cp
;
164 tls_cert_not_before(void * cert
, uschar
* mod
)
166 return asn1_time_copy(X509_get_notBefore((X509
*)cert
), mod
);
170 tls_cert_not_after(void * cert
, uschar
* mod
)
172 return asn1_time_copy(X509_get_notAfter((X509
*)cert
), mod
);
176 tls_cert_serial_number(void * cert
, uschar
* mod
)
179 BIO
* bp
= BIO_new(BIO_s_mem());
182 if (!bp
) return badalloc();
184 len
= i2a_ASN1_INTEGER(bp
, X509_get_serialNumber((X509
*)cert
));
185 if (len
< sizeof(txt
))
186 BIO_read(bp
, txt
, len
);
190 return string_copynlc(txt
, len
); /* lowercase */
194 tls_cert_signature(void * cert
, uschar
* mod
)
197 BIO
* bp
= BIO_new(BIO_s_mem());
199 if (!bp
) return badalloc();
201 if (X509_print_ex(bp
, (X509
*)cert
, 0,
202 X509_FLAG_NO_HEADER
| X509_FLAG_NO_VERSION
| X509_FLAG_NO_SERIAL
|
203 X509_FLAG_NO_SIGNAME
| X509_FLAG_NO_ISSUER
| X509_FLAG_NO_VALIDITY
|
204 X509_FLAG_NO_SUBJECT
| X509_FLAG_NO_PUBKEY
| X509_FLAG_NO_EXTENSIONS
|
205 /* X509_FLAG_NO_SIGDUMP is the missing one */
206 X509_FLAG_NO_AUX
) == 1)
208 long len
= BIO_get_mem_data(bp
, &cp
);
210 /* Strip leading "Signature Algorithm" line */
211 while (*cp
&& *cp
!= '\n') { cp
++; len
--; }
213 cp
= string_copyn(cp
+1, len
-1);
220 tls_cert_signature_algorithm(void * cert
, uschar
* mod
)
223 BIO
* bp
= BIO_new(BIO_s_mem());
225 if (!bp
) return badalloc();
227 if (X509_print_ex(bp
, (X509
*)cert
, 0,
228 X509_FLAG_NO_HEADER
| X509_FLAG_NO_VERSION
| X509_FLAG_NO_SERIAL
|
229 /* X509_FLAG_NO_SIGNAME is the missing one */
230 X509_FLAG_NO_ISSUER
| X509_FLAG_NO_VALIDITY
|
231 X509_FLAG_NO_SUBJECT
| X509_FLAG_NO_PUBKEY
| X509_FLAG_NO_EXTENSIONS
|
232 X509_FLAG_NO_SIGDUMP
| X509_FLAG_NO_AUX
) == 1)
234 long len
= BIO_get_mem_data(bp
, &cp
);
236 /* Strip leading " Signature Algorithm: " and trailing newline */
237 while (*cp
&& *cp
!= ':') { cp
++; len
--; }
238 do { cp
++; len
--; } while (*cp
&& *cp
== ' ');
239 if (cp
[len
-1] == '\n') len
--;
241 cp
= string_copyn(cp
, len
);
248 tls_cert_subject(void * cert
, uschar
* mod
)
250 uschar
* cp
= x509_name_copy(X509_get_subject_name((X509
*)cert
));
251 return mod
? tls_field_from_dn(cp
, mod
) : cp
;
255 tls_cert_version(void * cert
, uschar
* mod
)
257 return string_sprintf("%d", X509_get_version((X509
*)cert
));
261 tls_cert_ext_by_oid(void * cert
, uschar
* oid
, int idx
)
263 int nid
= OBJ_create(CS oid
, "", "");
264 int nidx
= X509_get_ext_by_NID((X509
*)cert
, nid
, idx
);
265 X509_EXTENSION
* ex
= X509_get_ext((X509
*)cert
, nidx
);
266 ASN1_OCTET_STRING
* adata
= X509_EXTENSION_get_data(ex
);
267 BIO
* bp
= BIO_new(BIO_s_mem());
273 if (!bp
) return badalloc();
275 M_ASN1_OCTET_STRING_print(bp
, adata
);
276 /* binary data, DER encoded */
278 /* just dump for now */
279 len
= BIO_get_mem_data(bp
, &cp1
);
280 cp3
= cp2
= store_get(len
*3+1);
284 sprintf(CS cp2
, "%.2x ", *cp1
++);
294 tls_cert_subject_altname(void * cert
, uschar
* mod
)
296 uschar
* list
= NULL
;
297 STACK_OF(GENERAL_NAME
) * san
= (STACK_OF(GENERAL_NAME
) *)
298 X509_get_ext_d2i((X509
*)cert
, NID_subject_alt_name
, NULL
, NULL
);
305 if (!san
) return NULL
;
309 if (*mod
== '>' && *++mod
) sep
= *mod
++;
310 else if (Ustrcmp(mod
, "dns")==0) { match
= GEN_DNS
; mod
+= 3; }
311 else if (Ustrcmp(mod
, "uri")==0) { match
= GEN_URI
; mod
+= 3; }
312 else if (Ustrcmp(mod
, "mail")==0) { match
= GEN_EMAIL
; mod
+= 4; }
319 while (sk_GENERAL_NAME_num(san
) > 0)
321 GENERAL_NAME
* namePart
= sk_GENERAL_NAME_pop(san
);
322 if (match
!= -1 && match
!= namePart
->type
)
324 switch (namePart
->type
)
328 ele
= ASN1_STRING_data(namePart
->d
.dNSName
);
329 len
= ASN1_STRING_length(namePart
->d
.dNSName
);
333 ele
= ASN1_STRING_data(namePart
->d
.uniformResourceIdentifier
);
334 len
= ASN1_STRING_length(namePart
->d
.uniformResourceIdentifier
);
338 ele
= ASN1_STRING_data(namePart
->d
.rfc822Name
);
339 len
= ASN1_STRING_length(namePart
->d
.rfc822Name
);
342 continue; /* ignore unrecognised types */
344 if (ele
[len
]) /* not nul-terminated */
345 ele
= string_copyn(ele
, len
);
347 if (strnlen(CS ele
, len
) == len
) /* ignore any with embedded nul */
348 list
= string_append_listele(list
, sep
,
349 match
== -1 ? string_sprintf("%s=%s", tag
, ele
) : ele
);
352 sk_GENERAL_NAME_free(san
);
357 tls_cert_ocsp_uri(void * cert
, uschar
* mod
)
359 STACK_OF(ACCESS_DESCRIPTION
) * ads
= (STACK_OF(ACCESS_DESCRIPTION
) *)
360 X509_get_ext_d2i((X509
*)cert
, NID_info_access
, NULL
, NULL
);
361 int adsnum
= sk_ACCESS_DESCRIPTION_num(ads
);
364 uschar
* list
= NULL
;
367 if (*mod
== '>' && *++mod
) sep
= *mod
++;
369 for (i
= 0; i
< adsnum
; i
++)
371 ACCESS_DESCRIPTION
* ad
= sk_ACCESS_DESCRIPTION_value(ads
, i
);
373 if (ad
&& OBJ_obj2nid(ad
->method
) == NID_ad_OCSP
)
374 list
= string_append_listele(list
, sep
,
375 ASN1_STRING_data(ad
->location
->d
.ia5
));
381 tls_cert_crl_uri(void * cert
, uschar
* mod
)
383 STACK_OF(DIST_POINT
) * dps
= (STACK_OF(DIST_POINT
) *)
384 X509_get_ext_d2i((X509
*)cert
, NID_crl_distribution_points
,
387 int dpsnum
= sk_DIST_POINT_num(dps
);
390 uschar
* list
= NULL
;
393 if (*mod
== '>' && *++mod
) sep
= *mod
++;
395 if (dps
) for (i
= 0; i
< dpsnum
; i
++)
396 if ((dp
= sk_DIST_POINT_value(dps
, i
)))
398 STACK_OF(GENERAL_NAME
) * names
= dp
->distpoint
->name
.fullname
;
400 int nnum
= sk_GENERAL_NAME_num(names
);
403 for (j
= 0; j
< nnum
; j
++)
404 if ( (np
= sk_GENERAL_NAME_value(names
, j
))
405 && np
->type
== GEN_URI
407 list
= string_append_listele(list
, sep
,
408 ASN1_STRING_data(np
->d
.uniformResourceIdentifier
));
415 /*****************************************************
416 * Certificate operator routines
417 *****************************************************/
419 fingerprint(X509
* cert
, const EVP_MD
* fdig
)
423 uschar md
[EVP_MAX_MD_SIZE
];
426 if (!X509_digest(cert
,fdig
,md
,&n
))
428 expand_string_message
= US
"tls_cert_fprt: out of mem\n";
431 cp
= store_get(n
*2+1);
432 for (j
= 0; j
< (int)n
; j
++) sprintf(CS cp
+2*j
, "%02X", md
[j
]);
437 tls_cert_fprt_md5(void * cert
)
439 return fingerprint((X509
*)cert
, EVP_md5());
443 tls_cert_fprt_sha1(void * cert
)
445 return fingerprint((X509
*)cert
, EVP_sha1());
449 tls_cert_fprt_sha256(void * cert
)
451 return fingerprint((X509
*)cert
, EVP_sha256());
457 /* End of tlscert-openssl.c */